There is at the present time no convenient and economical method of preparing products such as perfluorocarboxylic acids, perfluorosulfonic acid and other perfluoro functional compounds. These acids, for example, are used as wetting agents or surfactants and also as intermediate materials for making treating agents for textiles, leathers, or papers, or for making products having surfactive properties. The perfluorosulfonic acids can also be used as acid catalysts in various reactions, such as alkylations.
To date, these products have been principally prepared by electrofluoroination, as described in J. Chem. Soc. (1956), page 173, in U.S. Pat. No. 3,732,398, and in Ind. Eng. Chem. (1951) 43, 2332. However, this technique is hard to put into practice and in the case of heavy acids results in very slight yields.
A chemical process to obtain these compounds is described in J. Fluorine Chem. 1975 5 (3) 265, and involves the reaction of CO.sub.2 or SO.sub.2 with perfluoro magnesium compounds. This technique, which uses organo magnesium compounds, is rather delicate and difficulty to carry out on a commercial basis.